* Bogus struct stat64 for qemu-microblaze (user emulation)? @ 2014-07-16 4:02 Rich Felker 2014-07-16 8:36 ` Peter Maydell 0 siblings, 1 reply; 4+ messages in thread From: Rich Felker @ 2014-07-16 4:02 UTC (permalink / raw) To: qemu-devel; +Cc: microblaze-linux, musl, Stefan Kristiansson The qemu-microblaze definition of struct stat64 seems to mismatch the kernel definition, which is using asm-generic/stat.h. See: http://git.qemu.org/?p=qemu.git;a=blob;f=linux-user/syscall_defs.h;h=c9e6323905486452f518102bf40ba73143c9d601;hb=HEAD#l1469 http://git.qemu.org/?p=qemu.git;a=blob;f=linux-user/syscall.c;h=a50229d0d72fc68966515fcf2bc308b833a3c032;hb=HEAD#l4949 This seems to be causing a truncated-to-32-bit inode number to be stored in the location where st_ino should reside, and a spurious copy of the inode number to be written in a unused slot at the end of the structure. Is my analysis correct? Stefan Kristiansson and I found this while working on the or1k port of musl libc, where it seems our structure for the existing microblaze port is wrongly aligned with the qemu definition rather than the definition the real kernel is using. Before I try correcting this on our side, I want to make sure we're working with the right version. Rich ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: Bogus struct stat64 for qemu-microblaze (user emulation)? 2014-07-16 4:02 Bogus struct stat64 for qemu-microblaze (user emulation)? Rich Felker @ 2014-07-16 8:36 ` Peter Maydell 2014-07-16 15:59 ` Re: [Qemu-devel] " Rich Felker 0 siblings, 1 reply; 4+ messages in thread From: Peter Maydell @ 2014-07-16 8:36 UTC (permalink / raw) To: Rich Felker; +Cc: musl, QEMU Developers, microblaze-linux, Stefan Kristiansson On 16 July 2014 05:02, Rich Felker <dalias@libc.org> wrote: > The qemu-microblaze definition of struct stat64 seems to mismatch the > kernel definition, which is using asm-generic/stat.h. See: > > http://git.qemu.org/?p=qemu.git;a=blob;f=linux-user/syscall_defs.h;h=c9e6323905486452f518102bf40ba73143c9d601;hb=HEAD#l1469 > http://git.qemu.org/?p=qemu.git;a=blob;f=linux-user/syscall.c;h=a50229d0d72fc68966515fcf2bc308b833a3c032;hb=HEAD#l4949 > > This seems to be causing a truncated-to-32-bit inode number to be > stored in the location where st_ino should reside, and a spurious copy > of the inode number to be written in a unused slot at the end of the > structure. Sounds quite plausible -- we've had issues with other archs not having correct stat struct definitions in QEMU. I don't suppose anybody's done much testing of the microblaze linux-user code. > Is my analysis correct? Stefan Kristiansson and I found this while > working on the or1k port of musl libc, where it seems our structure > for the existing microblaze port is wrongly aligned with the qemu > definition rather than the definition the real kernel is using. Before > I try correcting this on our side, I want to make sure we're working > with the right version. I would definitely trust the kernel definition, not QEMU's! thanks -- PMM ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: Re: [Qemu-devel] Bogus struct stat64 for qemu-microblaze (user emulation)? 2014-07-16 8:36 ` Peter Maydell @ 2014-07-16 15:59 ` Rich Felker [not found] ` <20140716155957.GL17402-C3MtFaGISjmo6RMmaWD+6Sb1p8zYI1N1@public.gmane.org> 0 siblings, 1 reply; 4+ messages in thread From: Rich Felker @ 2014-07-16 15:59 UTC (permalink / raw) To: Peter Maydell Cc: QEMU Developers, musl, microblaze-linux, Stefan Kristiansson, Edgar E. Iglesias On Wed, Jul 16, 2014 at 09:36:23AM +0100, Peter Maydell wrote: > On 16 July 2014 05:02, Rich Felker <dalias@libc.org> wrote: > > The qemu-microblaze definition of struct stat64 seems to mismatch the > > kernel definition, which is using asm-generic/stat.h. See: > > > > http://git.qemu.org/?p=qemu.git;a=blob;f=linux-user/syscall_defs.h;h=c9e6323905486452f518102bf40ba73143c9d601;hb=HEAD#l1469 > > http://git.qemu.org/?p=qemu.git;a=blob;f=linux-user/syscall.c;h=a50229d0d72fc68966515fcf2bc308b833a3c032;hb=HEAD#l4949 > > > > This seems to be causing a truncated-to-32-bit inode number to be > > stored in the location where st_ino should reside, and a spurious copy > > of the inode number to be written in a unused slot at the end of the > > structure. > > Sounds quite plausible -- we've had issues with other archs > not having correct stat struct definitions in QEMU. I don't > suppose anybody's done much testing of the microblaze > linux-user code. The bug seems to have been introduced here. http://git.qemu.org/?p=qemu.git;a=commitdiff;h=a523eb06ec3fb2f4f4f4d362bb23704811d11379 I'm CC'ing the author/committer in case he has any input on why he did this. > > Is my analysis correct? Stefan Kristiansson and I found this while > > working on the or1k port of musl libc, where it seems our structure > > for the existing microblaze port is wrongly aligned with the qemu > > definition rather than the definition the real kernel is using. Before > > I try correcting this on our side, I want to make sure we're working > > with the right version. > > I would definitely trust the kernel definition, not QEMU's! Yes. Rich ^ permalink raw reply [flat|nested] 4+ messages in thread
[parent not found: <20140716155957.GL17402-C3MtFaGISjmo6RMmaWD+6Sb1p8zYI1N1@public.gmane.org>]
* Re: [Qemu-devel] [musl] Re: Bogus struct stat64 for qemu-microblaze (user emulation)? [not found] ` <20140716155957.GL17402-C3MtFaGISjmo6RMmaWD+6Sb1p8zYI1N1@public.gmane.org> @ 2014-07-17 23:39 ` Edgar E. Iglesias 0 siblings, 0 replies; 4+ messages in thread From: Edgar E. Iglesias @ 2014-07-17 23:39 UTC (permalink / raw) To: Rich Felker Cc: Peter Maydell, microblaze-linux-FR6EJeJVuqfA6Z3fQjNZrN9u6TNh0Fb7, musl-ZwoEplunGu1jrUoiu81ncdBPR1lH4CV8, QEMU Developers, Stefan Kristiansson, Edgar E. Iglesias On Wed, Jul 16, 2014 at 11:59:58AM -0400, Rich Felker wrote: > On Wed, Jul 16, 2014 at 09:36:23AM +0100, Peter Maydell wrote: > > On 16 July 2014 05:02, Rich Felker <dalias-8zAoT0mYgF4@public.gmane.org> wrote: > > > The qemu-microblaze definition of struct stat64 seems to mismatch the > > > kernel definition, which is using asm-generic/stat.h. See: > > > > > > http://git.qemu.org/?p=qemu.git;a=blob;f=linux-user/syscall_defs.h;h=c9e6323905486452f518102bf40ba73143c9d601;hb=HEAD#l1469 > > > http://git.qemu.org/?p=qemu.git;a=blob;f=linux-user/syscall.c;h=a50229d0d72fc68966515fcf2bc308b833a3c032;hb=HEAD#l4949 > > > > > > This seems to be causing a truncated-to-32-bit inode number to be > > > stored in the location where st_ino should reside, and a spurious copy > > > of the inode number to be written in a unused slot at the end of the > > > structure. > > > > Sounds quite plausible -- we've had issues with other archs > > not having correct stat struct definitions in QEMU. I don't > > suppose anybody's done much testing of the microblaze > > linux-user code. > > The bug seems to have been introduced here. > > http://git.qemu.org/?p=qemu.git;a=commitdiff;h=a523eb06ec3fb2f4f4f4d362bb23704811d11379 > > I'm CC'ing the author/committer in case he has any input on why he did > this. > > > > Is my analysis correct? Stefan Kristiansson and I found this while > > > working on the or1k port of musl libc, where it seems our structure > > > for the existing microblaze port is wrongly aligned with the qemu > > > definition rather than the definition the real kernel is using. Before > > > I try correcting this on our side, I want to make sure we're working > > > with the right version. > > > > I would definitely trust the kernel definition, not QEMU's! > > Yes. Hi, Yes, please trust the kernel. We had a state of flux for a while where various ABIs circulated, I don't remember the details. If you create a patch and try both mb little and big-endian that would be awesome. Thanks, Edgar > > Rich > _______________________________________________ microblaze-linux mailing list microblaze-linux-FR6EJeJVuqfA6Z3fQjNZrN9u6TNh0Fb7@public.gmane.org https://lists.eait.uq.edu.au/mailman/listinfo/microblaze-linux ^ permalink raw reply [flat|nested] 4+ messages in thread
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2014-07-16 4:02 Bogus struct stat64 for qemu-microblaze (user emulation)? Rich Felker
2014-07-16 8:36 ` Peter Maydell
2014-07-16 15:59 ` Re: [Qemu-devel] " Rich Felker
[not found] ` <20140716155957.GL17402-C3MtFaGISjmo6RMmaWD+6Sb1p8zYI1N1@public.gmane.org>
2014-07-17 23:39 ` [Qemu-devel] [musl] " Edgar E. Iglesias
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